Vitamin D and gestational diabetes: an update

Purpose of reviewVitamin D status (which is involved in glucose homeostasis) is related to gestational diabetes mellitus (GDM). GDM is characterized by increased resistance to and impaired secretion of insulin and results in higher risk of adverse pregnancy outcomes including operative delivery, macrosomia, shoulder dystocia and neonatal hypoglycemia. Women with GDM and their babies are at increased risk for developing type II diabetes.Recent findingsInternational definitions of vitamin D deficiency and normality are inconsistent. Vitamin D deficiency is common in pregnant women particularly those with poor diets and who have dark skins living in temperate climes with lack of exposure to sunlight.SummaryFew interventional studies indicate that supplementation optimizes maternal vitamin D status or improves maternal glucose metabolism. Observational studies about maternal vitamin D status and risk of GDM are conflicting. This could be because of measurement of vitamin D or differences in population characteristics such as ethnicity, geographic location, gestational age at sampling and diagnostic criteria for GDM. Good-quality randomized controlled trials are required to determine whether vitamin D supplementation decreases the risk of GDM or improves glucose tolerance in diabetic women.Univ Southern Denmark, Dept Gynecol & Obstet, Inst Clin, Odense Univ Hosp, Odense, DenmarkUCL, Div Surg, Northwick Pk Inst Med Res Campus, London, EnglandUniversidade Federal de São Paulo, Brazilian Cochrane Ctr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Internal Med, São Paulo, BrazilUniversidade Federal de São Paulo, Brazilian Cochrane Ctr, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Internal Med, São Paulo, BrazilWeb of Scienc